Device to regulate the driven flat friction wheels for the batch rolls of a dye jigger



6, 1970 kolcl-u YAMASHITA 3.488.012

DEVICE 'ro' REGULA'IE THE DRIVEN FLAT FRICTION WHEELS FOR THE BATCH ROLLS OF A DYE JIGGER Filed May 27, 1966 3 Sheets-Sheet 1 24 6| 63 E a k I T"! 30 I as "3 so as 58 23 a? l FIG.4 25

a was 55 i: 3 ['Q} -l H 2, 92

n Fla? INVENTOR. KO/CH/ YAMASHITR HIS R TTORNE Y3 3143.012 EELS Jan; 6, 1970 Kom-u YAMAsHIM DEVICE TO REGUL ATE THE DRIVEN FLAT FRICTION WH FOR THE BATCH ROLLS OF A DYE JIGGER 3 Sheets-Sheet 2 Filed May 27. i966 1970 KOICHI YAMASHITA 3,488.012

DEVICE TO REGULATE THE DRIVEN FLAT FRICTION WHEELS FOR THE BATCH ROLLS OF A DYE JIGGER Filed May 27. 1966 3 Sheets-Sheet 3 FIG.6

United States Patent 3,488,012 DEVICE TO REGULATE THE DRIVEN FLAT FRICTEON WHEELS FOR THE BATCH ROLLS OF A DYE JIGGER Koiehi Yamashita, Aichi-ken, Japan Filed May 27, 1966, Ser. No. 553,564 Claims priority, application Japan, May 31, 1965, 40/ 32,389 Int. Cl. B65h 23/20 US. Cl. 242-55 14 Claims ABSTRACT OF THE DISCLOSURE A control system for maintaining a predetermined constant tension and velocity of a fabric passing through a dye jigger during a winding process by the variation of the working radii of a pair of spaced eccentrically facing friction wheels each of which is drivingly associated with a batch roll of a dye jigger. An intermediate friction roller is located between the two friction wheels so as to slidingly engage their eccentrically disposed facing surfaces and vary the speed ratio of the batch rolls to effect constant tension in the fabric.

This invention relates to a device to regulate two driven friction wheels coupled respectively to two batch rolls of the dye jigger at constant tension and velocity of the fabrics.

In such a jigger with this device, it has no feeler in the batch rolls room, the tension and velocity of the fabrics are regulated by its own driving apparatus only. And so, these driving devices are used for not only the general jigger but also the supertensionless jigger having no dancing roller or scanning roller as shown in FIG. 1, and the high pressure jigger that is difficult to set such a feeler.

The invention consists in that a dancing friction roller is held between two flat friction wheels eccentrically facing each other, and the friction roller is driven by an AC. induction motor. In order to fulfill the basic condition of an analog drive of the rewinding process that is to keep similar respectively actual driven radii of two friction wheels and radii of two fabric batch rolls during the entire rewinding process, two friction wheels on the slide bases are guided to same direction right or left by a double-crank arrangement having the cranks set at right angles and both crank radii are variable at the same time. Automatic adjustment of the guide is effected by the electrical and mechanical proportional and integral control devices as following. During the regular rewinding process, the reaction to the friction roller and the fabric tension control steel yard balance are balancing each other. While the rewinding process is going on, the silicon controlled rectifiers amplifier and the DC. servomotor for the double crank arrangement are excited by a pair of electric phase shifters for the detection of the steel yard balance inclination due to the variation of the reaction. The bellows for absorbing the oscillation of the steel yard balance is an integral control device. The feeler of the automatic P.I. control device is the dancing friction roller biased by the steel yard balance weight. Mechanical losses from the friction wheels to the batch rolls are taken into account by the analog compensating device. At the beginning of the rewinding process, only one adjustment of both crank radii is performed so as to take measure of the maximum wound thickness of the fabrics on the roll, and so the actual values of the fabrics velocity and tension are equal to the values shown on their scales.

The invention is explained in detail by way of a pre- 3,488,012 Patented Jan. 6, 1970 ferred embodiment illustrated in mechanical and electrical schematic diagram in the accompanying drawings.

In these drawings:

FIG. 1 is a view which shows a jigger of the pendulous cloth guider type (Japanese Patent No. 405,068, publication No. 15,435/1962);

FIG. 2 is a schematic front view of the main and principal part of the present invention;

FIG. 3 is a schematic side view thereof;

FIG. 4 is a schematic plan view thereof;

FIG. 5 is a jigger analog circle diagram illustrating instantaneous radii of both fabric batch rolls;

FIG. 6 is a diagram which illustrates the control operation carried out in correspondence with the displacement of the movable cores of a pair of variable inductances; and

FIG. 7 is an electrical schematic diagram of a control circuit for DC. servo-motor control.

Now referring to FIGS. 2, 3 and 4, there is installed a driving shaft 26 in between and in parallel with two equal sized flat friction wheels 22 and 23 facing each other and being disposed eccentrically with each other, and further in the same plane there is disposed the central shafts 24 and 25 of the friction wheels. At one end 27 of this driving shaft 26 there are installed a V-belt pulley 28 and further the center of the V-belt pulley is concentrated on the center of the radial bearing holder 29 and further a friction roller 31 is fixed at the other end 30. Two pins 38 and 39 of a lever frame 37 which is able to swing around axes and 36 are inserted into two pin holes 33 and 34 on both sides of a friction roller side bearing 32 near the friction roller 31. Consequently the friction roller side bearing 32 can be swung in a small gap between upper and lower limit stopper rubbers 4t and 41 around the radial bearing holder 29. There is a connecting rod 42 coaxially in an upper vertical line passing through the center 30 of the friction roller. The lower end of the connecting rod 42 is connected with the upper portion of the friction roller side bearing 32 by a pin joint 43 in such a manner as to be free from the friction roller 31. The upper end of the rod 42 is connected by a pin joint 48 with one end of a tension control steel yard balance 44, the latter of which is supported by an intermediate pivot 45 and marked with a fabric tension scales 46 and provided with a suitably fitted slidable weight 47 thereon. Two pairs of rollers 49, 50 and 51, 52 are installed at the intermediate portion of the connecting rod 42, and a two chamber type bellows damper 54 and a movable core 56 of a pair of electric phase shifters are installed at the upper portion through a buffer spring 53.

Further, two coil springs 57 and 58 keep the pressures constant at two contact points 59 and 60 between the friction roller and the friction wheels and are set around the central shafts 24 and 25 of the friction wheels 22 and 23 respectively. Two V-belt pulleys 61 and 62 of the central shafts 24 and 25 are coupled respectively with the batch roll shafts 3 and 4 through reduction mechanisms 20 and 21 having V-belts, V-belt tension pulleys and gears. Two slide bases 63 and 64 which are set in parallel to the friction wheels and horizontally extended are fitted into sliding metal holes 67 and 68 of the journals and 66 of two friction wheels respectively. Now, there are many kinds of devices which act as a guider for regulating the friction wheels, for example, two cam mechanisms, one crank and two slider slots crossed at right angles, and others. For the convenience of the easy understanding of the principle, well known right angled double crank arrangement is shown here. Two crank pins and 76 of a crank disk 72 are fitted respectively into the slots of the slider frames which are fixed at the lower side of the journals 65 and 66 perpendicularly. The center of the crank disk 72 is loosely held by the fixed axis 71 which is set under the friction roller center 30 horizontally and in parallel with the surface of the friction roller 31. In the upper semi-circle of this crank disk 72 there are two adjustment threaded bars 73 and 74 which are set at right angles and in radial directions. Two nuts 77 and 78 having protruding crank pins 75 and 76 are fitted on these threaded bars respectively, and bevel gears 79 and 80 are fixed at the crank disk center side ends of these threaded bars. These bevel gears are always in gear with one side of a double-added toothed bevel gear 81 that is loosely held on the fixed axis 71, and a shaft 83 is held in a sliding journal 82. The gear 81 may be engaged with a bevel gear 84 that is fixed at one of the shafts 83 by pushing the handle 85 for adjustment to the maximum fabric wound thickness. The handle 85 is fixed at the other end of the shaft 83 and is pushed toward the fixed axis 71 by pressing a releasing spring 86. At this time, if the handle 85 is rotated, the bevel gears 79 and 80 are rotated at same time, consequently crank pins 75 and 76 are shifted keeping equal of the two distances from the center 87. An arrow 88 is marked on the nut 77, and there is a scale 89 on which is indicated the maximum fabric wound thicknesses along the displacement of this nut. Worm wheel teeth 90 along the lower side of the crank disk 72 are in gear with worm gear 91 that is coupled to the electric D.C. servomotor 92, and crank disk 72 is caused to rotate in either direction within the range of 90 degrees of angle by the rotating of the servomotor 92. The V-belt pulley 28 of the driving shaft is driven by a V-belt coupled with the stepped pulley 94 of the electric A.C. induction motor 93. After the fabric velocity has been adjusted by changing the V-belt to the other groove of the motor stepped V-pulley, in order to keep the angle formed by the V-belt and the driving shaft 26 always at approximately right angles, the motor 93 should be shifted axially and the velocity adjustment handle 96 fixed to the motor should be dropped into a suitable slot the stepped plate. The numerical values of the fabric velocities are marked on the slots of the stepped plate 95, and so the fabric velocity may be predetermined by the slot of the stepped plate.

Next, the structure of the compensating device for mechanical losses will be described. Tension springs 100 and 101 are provided at one end 99 of a horizontal lever 98 which is adapted to move around an axis 97. The springs are placed perpendicularly to the horizontal lever 98, one of the springs being set above the horizontal lever while the other in below. Other ends of the springs are connected to two electric plunger magnets 102 and 103 which actuate alternately when winding or unwinding. The other end of the horizontal lever 98 is adapted to slide in its direction through a gap of two rollers 49 and 50 installed at the intermediate portion of the connecting rod 42. This winding side compensating device for the winding side mechanical losses is mounted on the winding side journal 65 so that a distance between the contact point 104 of the horizontal lever 98 with the roller 49 and the axis 97 is always equal to a distance between the contact point 59 of the winding side friction wheel 22 with the friction roller 31 and the center 105 of the wheel. The unwinding side compensating device for the unwinding side mechanical losses is mounted on the unwinding side journal 66 facing the winding side compensating device and the manner and parts are similar to the winding side ones and designated by reference characters illustrated in the figures.

Next, the operation of the mechanism will be described.

In the sectional view of the roll of the dye jigger illustrated in the upper portion of FIG. 2, the'distance between the center 1 of the shaft 3 of the winding side batch roll and the point 11 where the fabric immediately before being wound contacts with the outer periphery 7 of the fabric wound around this roll, that is, the winding side fabric radius 1 to 11 be assumed to be 7' and the tension of the fabric 17 immediately before being wound is designated by vector 13 and T In the same way, the distance between the center 2 of the shaft 4 of the unwinding side batch roll and the point 12 where the fabric 18 immediately after being unwound contacts with the outer periphery 8 of the fabric wound around the batch roll 16, that is, the radius of unwinding side radius 2 to 12 is assumed to be r and the tension of the fabric 18 immediately after being unwound is designated by vector 14 and T Further, fabric tension caused by frictional loss of a roll 10 which represents guide rolls and expanders, etc. is designated by vector 15 and T Next, let 9 be the point where the maximum fabric outer periphery around the unwinding side roll intersects with the perpendicular erected from the center 2 upwardly, and let 19 be the point where the straight line between 2 and 9 intersects with the outer periphery of the batch roll 6. Further, we assume that:

Radii of both batch rolls R Maximum fabric wound radius from 2 to 9 R And the maximum fabric wound thickness from 19 to 9 X The intersection of the horizontal line passing through the center '2 with the outer periphery of the roll 6 is designated by 16.

In a so called regular rewinding of the jigger, a winding fabric velocity is always equal to an unwinding fabric velocity, and a sum of fabric quantities on two batch rolls is not varied, and so the sum of the sectional areas of two fabric batch rolls is constant. That is:

wherein we assume that Y= /R +R which is equal to the distance between (9) to (16). This will be termed as jigger analog radius for convenience of description.

From Equation 1, a circle diagram illustrated in FIG. 5 may be obtained.

Now in the upper semi-circle of the jigger analog circle with its radius Y==9 to 16, we erect a perpendicular from the center and define the point 117 at which the perpendicular intersects the circumference 116 of said circle. Then two straight lines starting from the center 115 and containing the perpendicular 117-115 therebetween and having a right angle therebetween at the center 115 are drawn, and their respective intersections with the circumference are designated by 118 and 119. From these two points 118, 119, the perpendiculars with respect to the horizontal line passing through the center 115 are drawn and their intersections are 120 and 121. Since the right angled triangular 115, 118, 120=the right angled triangular 119, 115, 121, assuming the distance between the points 120 and 115=r and the distance between the points 121 and 115=r the equation:

may be obtained from Pythagorean theorem and this equation is similar to Equation 1. We assume in this case the angle formed by 118, 115 and 120 be 0. v

' In case of FIG. 2, when rewinding process is going on, the angle 0 becomes smaller.

The crank disk 72 for operating the speed changer shown in the lower portion in FIG. 2 is similar to the jigger-analog circle diagram illustrated in FIG. 5, based upon the above described principle and the only difference is that its size is reduced by a fixed rate. The distance from the center 87 of the crank disk to the crank pin 75, that is the analog radius of a speed changer maybe defined as Y and further assuming the rate of reduction be K which is smaller than unity, that is K 1 Y /Y=K 2) therefore, from Equations 1 and 2, we have Q=KNW W The X scale 89 is marked at a position Y on the crank disk which has been chosen by the calculation utilizing Equation 3 by previously assuming a given maximum fabric wound thickness X Therefore, by effecting so called adjustment for maximum fabric wound thickness in which the arrow 88 located at the center of the crank pin is coincided with the scale marking on the scale 89 which is equal to the maximum fabric wound thickness measured at each time the fabric quantity to be loaded is changed, the rate of reduction K may be always kept constant.

Further, as is clear from the construction,

r (105)--(59)=(122)--(87) and r =(1l3)-(60)=(123) -(87) so that is held always true. This is completely similar equation as Equation 1.

Next, by using the friction type speed changer as shown in FIGS. 2, 3, and 4, the necessary condition which the fabric peripheral velocities on the both batch rolls may be made equal will be obtained.

We assume that the rpm. of the winding and unwinding rolls be It; and 11 the rpm. of the winding and unwinding side friction wheels be n and n the working radii of the winding and unwinding side friction wheels be r and r and the reduction ratio of the reduction mechanisms 20 and 21 be G. However, the reduction ratio G 1.

When the friction roller 31 is rotated at such a peripheral velocity V in the direction indicated by the arrow, two friction wheels are caused to rotate at the same time due to the construction hereinbefore described so that we have c= c1 c1 c2 e2 =ZL=B n 02 Fabric velocity of the winding side roll:

V =21rr n Fabric velocity of the unwinding side roll:

V =21rr n From the above equations, we have:

v =GV, 11

1 c1 and Tl V2 m (10) therefore, the necessary condition that V =V is:

D It (:1 T02 1 In the disk 72, we erect the perpendiculars from the winding and unwinding side crank pins 75 and 76 to the horizontal line passing through the center 87, and determine these two intersections are 122 and 123 and the angle 75, 87, 122 is H When the angle 6 in FIG. 5 is made equal with this angle 1%, as is clear from the equation of similar rightangled triangles; we have:

and therefore, Equation 11 is held true. From the above relationships, in order to keep the regular rewinding by utilizing the device of the present invention, it will be understood that the automatic control is required in which the increase or decrease in fabric tension produced by the difference between the velocities of the right and left side fabrics is detected; and the speed changer crank disk is always so rotated that the angle 0 in the jigger analog circle diagram may be made equal always with the angle 0 of the speed changer crank disk.

Now the equation of the fabric velocity V is from Equations 9, l0 and 12 In this equation, when the value of Y is maintained constant and only the fabric quantity is varied, the value of Y will be consequently varied. However, when the adjustment for maximum fabric wound thickness is performed as stated above and accordingly maintains Y /Y=K at a constant value, we have:

V=GV,,/K (13) Therefore, the fundamental speed of fabric will never be changed as long as the peripheral velocity V of the friction roller is remained unchanged even when the quantity of fabric is varied. That is, in the device of the present invention, the fundamental speed of fabric will not be varied if adjustment for maximum fabric wound thickness is performed when the quantity of fabric is varied, and remains equal to the numerical values indicated at the stepped plate for speed indication.

Next, the relation between the fabric tension 13 T of the fabric immediately before being wound, fabric tension 14 T of the fabric immediately after being unwound, and tension 15 T caused by the frictional loss of the roll 10 will be described. The frictional loss of the roll 10 is considered to be caused by dynamic friction coefiicient ,u, which in this case is considered to be constant, ,u=const. From FIG. 2, we have:

l= ERi+ 2 (14) TER=/"'(T1+T2) From the above two equations, we have T =K T (16) where:

K const. and

Next, the downward reaction exerted upon the friction roller side bearing 32 will be shown. However, in the present invention the reaction due to mechanical loss of the driving device is counterbalanced by means of the compensating mechanism, which will be described hereinafter, so that the such reaction will be neglected in this case.

Let the driving torques of the winding side and unwinding side rolls be 7'1 and 1' respectively and also let the component of the downward reaction f exerted upon the friction roller side journal 32 produced by T1 be f,, and the component produced by T2 be f then we have:

By substituting Equation 18 in the above equation, we have:

Now the description will be made with reference to the regular rewinding in which the friction roller 31 is driven in the direction indicated by an arrow at the peripheral speed V in such a condition indicated in FIGS.

3 and 4; the winding side fabric velocity and the unwinding side fabric velocity of the batch rolls are made equal with each other at the speed V; and the downward reaction F exerted upon the friction roller side bearing 32 corresponding to the fabric tension and the lifting force F exerted upon the pin 48 located at one end of the fabric tension control steel yard balance corresponding to the position of the slidable weight are balanced with each other so that the driving shaft 26 is maintained horizontally and a pair of movable cores of the variable inductance are located at the neutral position. In this case, :9 and Equation 12 is held true. By substituting Equation 12 in Equation 22,

This shows the equilibrium condition. That is, winding side fabric tension T is determined by lifting force F by means of the steel yard balance for controlling tension and is maintained constant as long as F is not varied. For example, when only the quantity of fabric is changed without changing Y the value of Y will be changed, and accordingly tension T is caused to vary even though F is kept constant. However, adjustment for maximum fabric wound thickness is performed as stated above and the Y Y=K is kept must, then we have:

From this, it will be seen that winding side fabric tension T is kept constant and its magnitude exactly corresponds with the fabric tension scale 46 as long as the magnitude F is not varied by displacing the slidable weight 47 on the steel yard balance for controlling the fabric tension even if the quantity of fabric is varied. In this case, this tension setting method of this invention employs the steel yard balance instead of springs so that the accuracy thereof is constant regardless of the variation of magnitude of tension, whereby tension variation rate of fabric is small even in case of low tension operation.

Just now, let us suppose the regular winding is carried out at the equilibrium conditions and next, let the winding process go on from this regular winding, then the radius of the winding side fabric batch roll r will become slightly larger and changed to r while the radius of the unwinding side fa'bric batch roll r will become slightly smaller and changed to 1' according to Equation 1. These variations are equivalent to a variation that 0 becomes slightly smaller and changed to 0', on the other hand, if the crank disc of the speed changer would not move and the inclination angle would remain its original magnitude 0 the equilibrium will be lost. In this case, V is slightly higher than the regular winding velocity and while V slightly lower, as a result, the fabric tension T is abruptly increased and the friction roller side bearing 32 is caused to move downwardly by the resultant force that the downward force according to Equation 22 overcomes to the lifting predetermined force due to the movable weight of the fabric tension control steel yard balance. Therefore, the movable core 56 of the electric phase shifter 55 is gradually lowered according to the time constant determined by the buffer spring 53 and the double oil chamber type bellows shock absorber 54.. This movement of the movable core 56 is converted into an electric power variation by an S.C.R. amplifier 114, and the DC. servomotor is driven so that the inclination angle 0 formed by 75, 87 and 122 of the crank disc 72 may be reduced. Thus the working radius r of the friction wheel 22 is increased and changed to 1' while the working radius l g of the friction wheel 23 is reduced and changed to r according to Equation 4. Finally the following equation may be established:

Hence:

Then the equilibrium condition is again restored and fabric tension T is caused to decrease, making so that the servomotor 92 is caused to stop, restoring the relation of V =V to the original magnitude V. When such processes are repeated, the machine is operating during a constant fabric velocity and tension for the entire rewinding process. In FIG. 6, the axis connecting 124 and 131 represent the upward displacement of the movable core 56 and the axis connecting 124 and 132 the downward displacement thereof. Further, the axis connecting 124 and 133 represents the forward running speed of the servomotor 92 while the axis connecting 124 and 134 the reverse running speed thereof. Even when the movable core 56 displaces from the neutral point 124 to the point located upwardly, the servomotor 92 will not be driven, but when the movable core 56 passes through this point 125, the motor 92 gradually starts forward running. When the speed of the motor reaches its maximum speed point 127, the voltage applied to the servomotor 92 reaches also its maximum value so that an over voltage delay relay 135 connected in parallel with the servomotor is caused to actuate so as to cut off the whole electric power supply, whereby the machine is caused to stop, thus preventing slackness of fabric.

On the other hand, when the movable core displaces downwardly, the servomotor 92 will never drive while the movable core passes along the line from the neutral point 124 and point 126. When the movable core passes after this point 126, the servomotor 92 is caused to start gradually for reverse running. When the speed of the motor reaches the maximum running speed point 128, another over voltage delay relay 135 is caused to actuate so as to cut off the whole electric power supply, in a similar way as stated above, thus preventing the fabric from being exerted by over tension. In this case, the tension determination method employs the steel yard balance, and so the fabric tension may be maintained constant with a higher accuracy at any range.

Hereinafter the description will be made regarding to a compensating method for the reaction exerted upon the friction roller side bearing 32 due to mechanical loss of the driving member.

In the high pressure jigger or the like, only torques due to fundamental mechanical loss -r and TMSZ of the mechanical seals of the winding side and unwinding side shafts are considered and such torque are supposed to beconstant. The increment of torque due to internal pressure increase is disregarded here.

And, in this case only torque 7G1 and TG2 due to fundamental mechanical losses in the winding and unwinding side reduction mechanisms are considered, and the increments of the torque due to transfer torque increase and r.p.m. increase are disregarded here.

We assume in this case that'mechanical losses in the winding and unwinding side driving mechanisms be converted into those produced in both of the batch roll shafts on the both sides, and that downward reactions exerted upon the friction roller side bearing 32 by above stated loss be designated by f and f respectively. Then we have:

Now, in order to eliminate these two reactions f and f it will be understood that the forces having the same magnitude with and the working direction opposite to the above stated reactions respectively must be exerted upon the friction roller side bearing 32. As illustrated in FIG. 2, plunger magnets 102 and 111 are actuated on the winding side an unwinding side respectively and others are idled, and when reversed, plunger magnets 103 and 112 are actuated and others are idled. Now, let us as sume that when the spring 100 or 101 is actuated, force W is generated, and when the spring 109 or 110 is actuated, force W is generated. Further suppose that the distance from the center of the axis 97 to one end 99 of the horizontal lever and the distance from the center of the axis 106 to one end 108 of the horizontal lever are equal and designated by Q. From the structural viewpoint, it is clear that 97 to 104 is r and 106 to 113 is 1'02, and let f and f be lifting forces exerted on the friction roller side bearing through the connecting rod 42 from the winding and unwinding side compensating device. Then, we have:

fbc" ,02

Further, in order that above forces may be counterbalanced with and f respectively, the following condition must be satisfied:

a faG Glr'i' Ms1) QW 01 el G fbG =fbc= T62:- W182):

Hence, the following equations must be held true:

Q a= G1+ MS1) Q b= G2+ MS2) The above stated relations are easily realized on the mechanisms by means of once adjusting of forces W and W produced by the four tension springs in a noload running of the jigger. After all, the reactions exerted upon the driving friction roller side bearing due to the mechanical losses in the driving mechanisms are counterbalanced respectively with the forces f and f produced by the compensating device. Therefore, the fabric tension can be kept constant even when small tension operation is carried out.

I claim:

1. In a driving device for automatically maintaining a predetermined constant tension and velocity of a fabric passing through a dye jigger during a winding process; means comprising in combination, a driving dancing friction roller disposed between and in point contact with two driven flat friction wheels eccentrically facing each other and being of equal size, said friction wheels being in mutually cooperative association with two fixed slide bases, gear means mechanically connecting said fiat friction wheels to two batch rolls of the dye jigger, a constant speed motor and said dancing friction roller being driven about a first axis by said constant speed motor and being capable of swinging in a small gap between upper and lower limit stops disposed about a radial bearing holder, a shaft supporting said dancing friction roller, one end of which is guided by said radlal bearing holder; means for comparing a predetermined active force with the fabric tension to produce a resultant control force, and means for moving said fiat friction wheels parallel to said first axis by an amount proportional to said control force whereby the fabric tension is maintained at a substantially constant value during the winding process.

2. The driving device according to claim 1, wherein a friction roller side bearing is provided about the end of said shaft connected to said dancing friction roller, and a connecting rod connected by pin means to said driving friction roller side bearing and one end of a pivotal steel yard balance.

3. The driving device according to claim 2, herein said means for comparing a predetermined active force with the fabric tension comprises an amplifier, a servomotor driven by said amplifier, a movable core disposed within a pair of electric phase shifters providing excitation of said amplifier, whereby the movement of said core corresponds to a slight shifting displacement of said connecting rod due to the resultant control force.

4. The driving device according to claim 3 wherein said device further includes a crank disc having two crank pins fitted respectively into two slider slots, disposed radially in said crank disc and at right angles with respect to each other.

5. The driving device according to claim 4, wherein gear means are provided between said crank disc and said servomotor so that said crank disc is caused to rotate in either direction within a range of about of angle by the the rotation of said servomoter, and wherein said crank disc is disposed under the center of said friction roller and parallel to the surfaces of said friction wheels.

6. The driving device according to claim 5, wherein said gearing means comprises a segmental 90 worm wheel disposed about the periphery of said crank disc and a worm is provided about a shaft extending from said servomotor.

7. The driving device according to claim 5 herein said two fixed slide bases are horizontally disposed and parallel to said friction wheels so as to provide guided paths for the movement of said two journals which are disposed thereabout and which support said two friction wheels, said journals having upper and lower extending arms, said lower extending arms having elongated slots and being in cooperative association with a double crank arrangement of said crank disc by means of the two slider crank pins which fit respectively into said two elongated slots of the lower extending arms, said two slider crank pins extending outwardly from nuts provided about threaded adjustment bars, and means capable of simultaneously adjusting the radii of said crank pins.

8. The driving device according to claim 7, wherein said steel yard balance weight establishes said predetermined active force and said force is compared with a signal force which is a function of the sum of reaction due to fabric tension at both contact points of said driving dancing friction roller with said two fiat friction wheels whereby the resultant control force which is produced is fed into said servomotor and associated amplifier so as to apply any necessary displacement of said connecting rod to insure that the ratio of the actual radii of said two friction wheels is substantially equal to the ratio of the radii of said two fabric batch rolls.

9. The driving device according to claim 8, including a pair of compensating mechanisms so as to compensate for the mechanical losses of the various mechanisms between said fiat friction wheels and said fabric batch rolls.

10. The driving device according to claim 9, wherein said compensating mechanisms each comprise two biasmg springs, a horizontal lever pivotable about an axis; said two biasing springs being separately connected between one end point of said pivotable lever, electrically operated plunger magnets oppositely disposed but not securedto upper and lower sides of said end of said lever but being mechanically connected to said springs, each of said magnets being alternately actuated, and the other end of said lever being adapted to freely slide between a pair of rollers which are disposed and attached to the central portion of said connecting rod; each of said compensating mechanisms being mounted onto and forming a part of said sliding journals such that the distance between the contact point of said rollers with said pivotable lever and said axis is always equal to the working radius of said one 1 1 driven flat friction wheel, whereby said mechanical losses are counterbalanced by initiallyadjusting said two springs.

11. The driving device according to claim 9, wherein means are provided for indicating the absolute value of the constant tension exerted on said fabric prior to being wound and means are provided for indicating the absolute value of the constant velocity of said fabric.

12. The driving device according to claim 11, wherein said means for providing the indication of the absolute value of the constant tension exerted on said fabric comprises a marked scale on said steel yard balance and a biasing weight for overcoming the inclination of said steel yard balance and a crank provided in said crank disc for adjusting the radii of said crank pins corresponding to the maximum fabric wound thickness on said batch rolls.

13. The driving device according to claim 12, wherein said means for indicating the absolute value of the constant velocity of said fabric comprises an adjustable speed control device for said constant speed motor.

I 14. The driving device according to claim 12, wherein said crank is slidably journaled in said crank disc and engageable with said threaded adjustment bars so as to position and arrange said crank pins of said nuts to have the same distance from the center of said crank disc, and arrow marking means on one of said nuts coincident with a scale placed along side the radial displacement of said nut, the displacement of said unt representing the magnitude of the maximum fabric wound thickness according to the following equation:

where References Cited UNITED STATES PATENTS 3,161,371 12/1964 Kuhn et a1 242-75.43 3,294,336 12/ 1966 Rotter 242--67.4 3,306,549 2/ 1967 E'berhardt et a1. 24267.5 1,981,370 11/1934 Mowat 24255.14 2,914,266 11/1959 Conncll 24255.l4

LEONARD D. CHRISTIAN, Primary Examiner US. Cl. X.R. 242-67.5 

